accumulator: Meaning and Definition of

ac•cu•mu•la•tor

1. a person or thing that accumulates.
2. a register or electric device on an arithmetic machine, as an adding machine, cash register, or digital computer, that receives a number and produces and stores the results of arithmetic operations of the given number with other numbers.
3. a storage battery or storage cell.
4. an apparatus that stores fluid at approximately the working pressure of the hydraulic or pneumatic system in which it will be employed, so that a supply of fluid is always immediately available to the system.
5. (in a boiler) a vessel for storing hot fluid, ready to flash into steam.
6. a vessel in which air is trapped and compressed by the liquid, thus storing energy to supply liquid under pressure when the demand of the system is greater than the capacity of the pump.